ash901226

since your only asking for the value of Cadj, what i can say is that if you really read the datasheet you will find on page 9 this info

Quote

External CapacitorsInput bypass capacitor Cin may be required for regulatorstability if the device is located more than a few inches fromthe power source. This capacitor will reduce the circuit'ssensitivity when powered from a complex source impedanceand significantly enhance the output transient response. Theinput bypass capacitor should be mounted with the shortestpossible track length directly across the regulator's inputand ground terminals. A 10 micro F ceramic or tantalumcapacitor should be adequate for most applications.

well basically the higher the value of the cap, the immune it is toward variation of input voltage ripple

Iadj should be in the datasheet for the device. It's a fixed amount which is very small.The output voltage is determined by R1 and R2.

The line from the output through R1 and R2 to ground, forms a voltage divider circuit which ismeasured by the bottom connection on the chip, to regulate the output voltage.

The Iadj in the equation, is an adjustment to the voltage divider equation, to compensate forthe small current going into the voltage sensing connection of the regulator chip.

I am not sure what Cadj is for at all.

If you are trying to make 4.3V, make sure you read about how much Vin has to be, compared to Vout.It has to be 0.7V or 1 volt more than Vout, that will also be in the datasheet. You might not be ableto get 4.3V from a 5V supply.